Furnace.



R. D. WHITING.

FURNACE.

APPLICATION FILED FEB. 12. 1917.

1,258,843. Patented Mar. 12, 1918.

2 SHEETS-SHEET I.

fl' a'heaa, Jim

R. D. WHITING.

FURNACE. APPLICATIOH FILED FEB- IZ' 19H- 4 Patented Mar.12,1918.

2 SHEETS-SHEET 2- :aIrZ n Az WRITING, or

FURNACE.

To all whom it may concern.

"Be it known that 1, Roy DIAz VVHITING, a citizen of the United. States, residing in the city of Chicago, county of Cook, and State of Illinois, have invented certain new and useful Improvements in Furnaces, of which the following is a specification.

This invention relates to furnaces and refers more particularly to means for obtaining a more perfect combustion of the fuel in the. fire zone.

Among the salient objects of the invention are to introduce air or other oxygen-con taining ga into the fire zone below the grate Because of the reduced air supply and the reduction of velocity through the gas passages, the efiiciency of. combustion. is increased. In practical operation, the ash pit member are throttled and the damper nearly closed so as to prevent excess of draft and excess rush of air through the furnace. The manner of introducing the air into the fire zone is important. The air is introduced into the heat zones through the air heaters located in the rear of the bridge wall or adjacent the bridge wall. These retorts are preferably made of fire brick so as to retain the heat and also prevent destruction, to which a metal pipe is liable. The air i caused to pass through the retorts a sufficient distance to highly superheat the air, the purpose being to introduce the air into the fire zone with as high heat as is practical.

I have further discovered that'where the air is introduced through the pipe or other conduit of uniform diameter that there is a pronouncedtendency for an air pocket to form along the wall of the retort or preheater, resulting in a cold or insufficiently heated stream of air passing through the Center of the pipe or conduit. Such stream Specification of Letters Eatent. Application filed February 12,1917; Serial No. 148,032.

Patented Mar. 12, 1 918.-

of air, of course, cannot'be effectively heated under such conditions. To obviate this it is'very advisable that the air currents be broken up, preferably by' placing obstructions in the conduit, thus preventing the clinging of the heated air to the outer walls of the conduit. This is a feature of thepresent invention. v

The advantages in distributing the air pipes under the grate instead of over the grate is that the passing of the air upwardly under the grate causes it to come in contact with the latter and breaks up'the air, the

grate members of the fuelbed acting in effect as baflies; If the air were introduced over the fuel bed, there would be artendency for the air to stratify and escape over the bridge wall instead of being intimately mixed with the combustion gases. The features of breakingup the preheated currents of air in the manner just described and the distributing of the air in unequal amounts at various parts of the fire zone are distinguishing features of thepresent inven tion.

Describing now the. apparatus shown in the drawings for a clearer illustration of the invention,

Figure 1 is a vertical sectional view of a fire box boiler equipped with my invention, parts being broken away to show interior construction and to reduce the size of the drawing.

Fig. 2 is a longitudinal sectional View taken on lines 2--2 of Fig. l and looking in the direction of the arrows. I

Fig.- 3 is an enlarged top lan view of one of the air heaters and its elivery pipe.

Fig. 4 is a side elevation of the same. 7

Fig. 5 is a sectional viewtaken on lines 5 -5 of Fig. 4, and looking in the direction of the arrows.

Fig. 6 is a sectional view taken on lines 66 of Fig. and looking in the direction of thearrows. I r

Fig. 7 is a detailed, view of the damper for controlling the inlet to the air heater.

Referring to the drawings, 1 designates as a whole the brickwork, 2 the fire box, 3 the grate, 4 the bridge wall, 5 the ash pit, 6

the ash door, 7 the fire box door, 8 the combustion chamber, 9 the fire tube boiler, 10 the stack, and 11 the damper controlling the stack. 12 designates one of the supports for the rear end of the boiler. At the rear of the boiler shell are the air heaters 13. Each of these air heaters is preferably formed of hollow fire brick 14, into three passages 15, 16, and 17, which communicate with each other through ports 18 and 19. Air is admitted to the lower passage 17 through suitable conduit 20, controlled by damper 21. In each of these passages or conduits of the air heater is mounted a plurality of baffle members 22, the detailed construction of which is shown more particularly in Figs. 5 and 6. These baffle members are preferably made of fire brick, asbestos rope or the like. The arrangement of these baffle members is such as to produce a swirling action of the air in each of the passages of the air heater, so that all of the air is caused to contact with the heater walls for a suthcient length of time to insure thorough heating with a minimum amount of actual obstruction to the passages.

To this end the baffle members are arranged in the form of inclined ribs projecting from the opposite walls of the passage a distance materially less than one-half the width of the passage and the ribs on one side wall of a passage are inclined reversely relative to those on the other side.

I prefer to dispose part of the ribs on opposite walls directly opposite each other, as shown in the two outside passages, Fig. 6, and part of the ribs on opposite walls staggered with relation to each other as shown in the intermediate passage. Thevair is delivered from theheater into a delivery pipe 23. Each of these pipes 23 is provided with air introduced to the fire at the rear of the rear to the forward end of the pipe.

There may be a number of ports of the same diameter as 24, the next of reduced diameter as 25 and so on down to the smallest ports 28. The dimens ons of these ports or 'per forations can be varied to suit local conditions but the largest one should always be at the rear of the fire zone so that the largest amount of air is introduced at the rear for the purposes heretofore described.

The position of the air heater may be varied except that it should be at or near the rear of the bridge wall. In certain cases, one air heater with its pipe extending centrally below the grate can be used but in any event, the largest amount of air should be the fire box. 7 V

The operation of the device should be apparent from the foregoin description and need not be described in detail.

I claim as my invention:

7 In a furnace the combination with a fire box and combustion chamber and bridge wall therebetweem'of an air heater in rear of the bridge wall comprising a plurality of passages having substantially parallel walls, baffles in said passages comprising inclined ribs projecting from the walls of said passages, the ribs on the wall of one passage being inclined reversely to those on the opposite wall of said passage, and means for conveying the air from said heater to the fire box.

BUY DIAZ WHI'IING.

Gepies of this patent may be obtained for five cents each. by addressing" tne eommissioner of Patents,

Washington, B. M 

